Updating a record consists of changing its value for
a particular column. To visually update a record, open the table to show
its records, locate the value that needs to be updated and edit it.

To update a record using SQL:

In the Object Explorer of Microsoft SQL Server Management Studio, you can right the table, position the mouse on
Script Table As -> UPDATE To -> New Query Editor Window

Open an empty query window and type your code

To support record maintenance operations, the SQL provides the UPDATE keyword
that is used to specify the table on which you want to maintain the
record(s). The basic formula to use is:

UPDATE TableName
SET ColumnName = Expression

With this formula, you must specify the name of the
involved table as the TableName factor of our formula. The SET
statement allows you to specify a new value, Expression, for the
field under the ColumnName column.

Updating all Records

Imagine that, at one time, on a particular table, all
records need to receive a new value under one particular column or certain
columns. There is no particular way to visually update all records of a
table. You can just open the table to view its records, and then change
them one at a time.

In SQL, the primary formula of the UPDATE statement as introduced
on our formula can be used to update all records. Here is an example:

To edit a record, first open the table to view its records.
Locate the record, the column on which you want to work, and locate the value
you want to change, then change it.

In SQL, you must provide a way for the interpreter
to locate the record. To do this, you would associate the WHERE operator
in an UPDATE statement using the following formula:

UPDATE TableName
SET ColumnName = Expression
WHERE Condition(s)

The WHERE operator allows you to specify how the
particular record involved would be identified. It is very important, in
most cases, that the criterion used be able to uniquely identify the record. In
the above table, imagine that you ask the interpreter to change the released
year to 1996 where the director of the video is Rob Reiner. The UPDATE statement
would be written as follows:

UPDATE Videos
SET YearReleased = 1996
WHERE Director = 'Rob Reiner';

In the above table, there are at least two videos directed
by Rob Reiner. When this statement is executed, all video records whose director
is Rob Reiner would be changed, which would compromise existing records that did
not need this change. Therefore, make sure your WHERE statement would isolate
one particular record or only those that need to be updated. Here is an example
used to change the name of the director of a particular video: